1. Field of the Invention
This invention relates to production of kanamycin C and its deoxy derivatives from kanamycin B or deoxy derivatives of the latter. This invention further relates to deoxy-kanamycin C derivatives which are new compounds useful as semi-synthetic aminoglycosidic antibiotics.
More particularly, this invention relates to a process for the production of kanamycin C, 3'-deoxykanamycin C and 3',4'-dideoxykanamycin C which are represented by the following general formula (I): ##STR1## where R.sub.1 and R.sub.2 are both hydroxyl, or R.sub.1 is hydrogen and R.sub.2 is hydroxyl, or R.sub.1 and R.sub.2 are both hydrogen. This invention also relates to the new deoxy-kanamycin C derivatives, that is, 3'-deoxykanamycin C which is the compound of the formula (I) where R.sub.1 is a hydrogen atom and R.sub.2 is hydroxyl group, and 3',4'-dideoxykanamycin C which is the compound of the formula (I) where R.sub.1 and R.sub.2 are both a hydrogen atom.
2. Description of the Prior Art
We, the present inventors, have made research on new semi-synthetic derivatives of aminoglycosidic antibiotics on the basis of the previous findings which were obtained by H. Umezawa et al. with respect to the mechanism of resistance of bacteria to aminoglycosidic antibiotics owing to various inactivating enzymes produced by the resistant bacteria. For instance, 3',4'-dideoxykanamycin B and 3'-deoxykanamycin B were synthetized as the deoxy derivatives of kanamycin B which are active against the resistant bacteria producing aminoglycoside 3'-phosphotransferases (see U.S. Pat. Nos. 3,753,973 and 3,929,762; H. Umezawa's "Advances in Carbohydrate Chemistry and Biochemistry" Vol. 30, page 183 (1974); and "Drug Action and Drug Resistance in Bacteria" Vol. 2, page 211 (1975)). 3',4'-Dideoxykanamycin B has been used widely in therapeutic treatment of infections caused by a variety of the resistant bacteria, including Pseudomonas aeruginosa. However, it has been found that these deoxy derivatives of kanamycin B can be inactivated by aminoglycoside 6'-acetyltransferases capable of acetylating the 6'-amino group of the deoxykanamycin B molecule and hence are not able to inhibit the growth of such resistant bacteria producing 6'-acetyltransferases.